σ/σ-和π/π-相互作用同样重要:多层石墨烯
Andrey A Fokin1, Dennis Gerbig, Peter R Schreiner
1Department of Organic Chemistry, Kiev Polytechnic Institute, 37 Pobeda Avenue, Kiev 03056, Ukraine. aaf@xtf.kpi.ua
Journal of the American Chemical Society
|November 9, 2011
概括
这项研究探讨了石墨烯和石墨烯,揭示了较大的结构表现出更接近散装材料的特性. 范德瓦尔斯复合体表现出强烈的关联能量,表明了分层结构和量子束效应.
科学领域:
- 计算化学的计算化学
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
背景情况:
- 石墨烯和石墨烯是具有独特电子和结构性质的二维碳异构体.
- 了解它们在单片,双层 (diamondoids) 和多层范德瓦尔斯 (vdW) 复合体中的行为对于材料设计至关重要.
研究的目的:
- 为了研究[n]graphanes,diamondoids和多层[n]graphanes的结构和电子特性.
- 为了将这些特性与它们的母[n] 石墨烯系统进行比较.
- 分析系统大小和分层对协会能量和电子带间隙的影响.
主要方法:
- 使用B97D/6-31G (d,p) 的分散校正密度函数理论 (DFT) 计算.
- 使用M06-2X/6-31G(d,p),B3LYP-D3/6-31G(d,p) 和SCS-MP2/cc-pVDZ单点能量的比较计算.
- 研究的系统大小在n = 10到97为石墨烯,n = 10到130为石墨烯.
主要成果:
- 石墨烯的范德瓦尔斯复合物表现出显著的关联能量,在 [97] 石墨烯二元体中达到120 kcal mol-1.
- 石墨烯表现出量子束效应,HOMO-LUMO间隙从8.2 eV ([10]石墨烯) 减少到5.7 eV ([97]石墨烯),接近散装值.
- 石墨烯和石墨烯都显示带间隙随着系统大小的增加而减少,石墨烯二元体接近二维金属特性.
结论:
- 层状石墨烯结构在能量方面有利,并表现出与系统大小相聚的电子性质.
- 层状石墨烯和钻石体的电子特性在1nm的粒子大小时变得相似.
- 该研究提供了对石墨烯和石墨烯系统尺寸依赖的电子和结构特征的见解.
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